Electronic components, in particular higher powered computer chips, are becoming more powerful and, consequently, need greater cooling capacity to run properly and durably. Air cooling systems are inherently limited in cooling capacity, and liquid systems, made up of a liquid heat exchanger in close proximity to the component, a pump, and an air to liquid heat exchanger exchanging heat with the ambient, are finding increasing use. Such systems need to be filled, at the time of manufacture, with liquid coolant, meaning that all of the components and lines need to be fully filled and bled of air. Typically, an in line coolant reservoir would be used both to provide a continual supply of make up coolant and to allow air in the system to be continually bled off, much like the reservoirs used in conventional vehicle engine cooling systems. It would be preferable to fill and seal the system air free on a one time basis, with a more compact fill valve, rather than provide a bulky and expensive reservoir.
A known fill and bleed valve for a computer chip liquid cooling system uses a set of three rotary valves, one central valve that interrupts the main cooling line, and two rotary fill valves, one to either side of the main shut off valve, that open up a fill inlet and fill outlet port into the system to allow an initial coolant fill to be pumped into, through, and finally out of the system components and lines. Clear lines in the vicinity of the rotary valves provide a visual indication of enough liquid having been pumped in and through the system to displace all entrapped air. That done, the two rotary fill valves can be shut off, and the intermediate main valve re opened. Three separate valves and rotary actions are themselves somewhat bulky and expensive. Furthermore, depending on the level, relative to the fill inlet and outlet points, of the length of system line located between the inlet and outlet points, some air may be trapped and not be totally purged by the fill.